Apparent “Krider’s” x “Eastern” Red-tailed Hawk, Pownal, Maine, 4/20/21

This stunningly pale immature Red-tailed Hawk passed over the Bradbury Mountain Spring Hawkwatch, sponsored by Freeport Wild Bird Supply, in Pownal, Maine on the afternoon of April 20, 2021.

Highly suggestive of the extremely pale “Krider’s” Red-tailed Hawk (a subspecies or quite possibly just a very pale color morph) from Central North America and with scattered vagrant records along the Eastern seaboard, we believe this individual shows features most consistent with an “intergrade” between the so-called Krider’s and our typical Eastern subspecies.

The very pale white head first brought my attention to this bird as it approached the summit from the north-northeast, and circled overhead and slightly behind the plethora of counters and observers on our biggest flight day of the season. Tova Mellen gets the award for the best photos – by far – and we appreciate her effort and willingness to share them. Thanks, Tova!

Andrew Sharp, Mathew Gilbert, and Charles Duncan also managed photos, and I was able to capture (poorly!) a few additional angles that show some helpful features.

The mostly-white head, very pale underparts, and lightly-marked underwings (especially the reduced patagium) all suggest Krider’s. However, the darker crown and fairly-dark spots on what would be the edges of the belly band are more suggestive of an intergrade.

The relatively bold white panel on the upperwings is also suggestive of Krider’s, but it’s not as bold and bright as many photos suggest. The back color is also brownish-gray. Both of these look to be more consistent with an intergrade.

The white uppertail coverts/lower rump area was more evident than this too-dark photo suggests, nonetheless, it does not seem white and broad enough to be a Krider’s. Unfortunately, the pattern of the uppertail was not decipherable.

The poor exposure of this photo makes the bird look much darker than it appeared in the field (looked more like Tova’s photos, above), but it does accentuate where the dark markings are and are not.

As for printed references, this bird looks to be a near-perfect match for the “Juv/1st Year Eastern x Krider’s Integrade on Page 66 of The Crossley ID Guide to Raptors.

We had limited views of the upperparts, but they did suggest the presence of fairly extensive white on the scapulars, the large pale window, and the narrow pale uppertail covert band as shown on page 293 of Raptors of Eastern North America by Brian K. Wheeler.

Therefore, we reached the tentative conclusion that this bird was an Eastern x Krider’s, but as with all subspecies and especially hybrid thereof, designations of Red-tailed Hawk, absolute identification is likely impossible. Fun bird though!

I’ll add any comments and feedback I receive here:

3 thoughts on “Apparent “Krider’s” x “Eastern” Red-tailed Hawk, Pownal, Maine, 4/20/21

  1. Pingback: Derek’s Birding This Week, 4/17-23/2021 | Maine Birding Field Notes

  2. Jack Rogers

    Your notes are very interesting. Thanks. Just a photo tip. You can adjust the exposure on hawk photos using exposure compensation. I’d suggest maybe +2 stops. Your images will show the plumage and colors much better. In auto mode your camera is exposing for the bright sky so the birds look almost black being underexposed.

    Reply

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